In May 2013, when I became commander of U.S. European Command and NATO’s supreme allied commander for Europe, I found U.S. and NATO forces well suited for their requirements at the time but ill prepared for the challenges that lay ahead. The United States’ military presence in Europe, which had shrunk significantly since the 1990s, was not oriented toward a specific threat. NATO, for its part, was mostly involved in operations outside the continent, primarily in Afghanistan.

Now that I have completed my tenure, I have the chance to reflect on how U.S. European Command and NATO have evolved since I took up my positions. Over the past three years, the United States and the alliance have shifted their focus to threats closer to the heart of Europe—namely, Russian aggression and the vexing challenges associated with the ongoing instability in the Middle East and North Africa. These threats are of a breadth and complexity that the continent has not seen since the end of World War II. Although the United States and NATO are better prepared to confront them today than they were in early 2014, when Russia illegally annexed Crimea and con­ducted a de facto invasion of eastern Ukraine, there is much more that the United States and its allies must do—above all, improve their abilities to deter the Russian threat and to deal with the problems associated with regional instability on Europe’s borders, namely, inter­national displacement and transnational terrorism. To better prepare for these challenges, the United States should increase the resources available to its forces in Europe and recognize Russia as the enduring, global threat it really represents.

Rafael Marchante / REUTERS

NATO soldiers during a military exercise near Setubal, Portugal, October 2015.

THE ROAD TO THE PRESENT

To appreciate the position the United States and its allies found themselves in when Russia began its intervention in Ukraine, it is helpful to look back to the Cold War. In the final years of that